The invention relates to a printed product slow down apparatus and method for use in a folder of a printing press, and more particularly, to a printed product slow down apparatus and method for slowing down individual printed products by contacting a portion of a printed product that is already in a pocket of a rotating bucket assembly.
In the printing industry, an image is repeatedly printed on a continuous web or substrate such as paper. The ink is dried by running the web through curing ovens. In a typical printing process, the web is subsequently slit, typically in the longitudinal direction which is the direction of web movement, to produce a plurality of continuous ribbons. The ribbons are aligned one on top of the other, folded longitudinally, and then cut laterally to produce a plurality of multi-paged, approximately page length web segments, termed signatures. A signature can also be one printed sheet of paper that has or has not been folded.
It is often desirable to transport successive signatures in different directions along various paths in the folder in order to increase the overall operating speed and versatility of the printing process. In general, a sheet diverter operates to route fast moving signatures along a desired one of a plurality of paths as the signatures continue on in the signature processing system. The diverted signatures are transported to one of a plurality of rotating bucket assemblies. The bucket assemblies are operable to transport individual signatures to a conveyor, typically in a shingled orientation. Generally, individual signatures are directed into a pocket of a rotating bucket assembly and, as the bucket assembly rotates, the signatures are removed from the pockets one individual signature after another onto the conveyor in an overlying or shingled orientation.
Printing press systems are operable at high speeds, typically in excess of 2,000-3,000 feet per minute. It is desirable to run printing press equipment at the highest speeds possible in order to produce as many printed products as possible in a given amount of time. Because printing presses operate at high speeds, it is usually necessary to reduce the speed of the signatures at some point in the folder in order to reduce damage to the signatures and to shingle the signatures on the conveyor adjacent the rotating bucket assemblies.
Without signature decelerating equipment, in order to avoid damage to the signatures as the signatures are transferred into the pockets of the rotating bucket assembly, the speed of each signature must be generally slowed down by running the printing press and folder at a slower rate of speed so that the impact force of the leading edge of the signature against the dead end of the pocket is reduced. Thus, without a slow down mechanism, reduced operating speeds limit the overall output of the printing system.
Signature slow down mechanisms often damage the signature they are slowing down. Crumpling of the leading or trailing edges of the signatures can occur if the slow down mechanism is too aggressive in slowing down the signatures.
Signature slow down mechanisms often have problems relating to correctly timing the transfer of the signatures from the slow down step to the entry into the pockets of the rotating bucket assembly. If a signature emerging from a slow down mechanism is not properly aligned with a pocket of the bucket assembly at the appropriate time, the signature will be directed at the bucket assembly in such a way that the signature will not properly enter a pocket which may cause a jam in the overall operation or damage to the signature.
The invention provides an apparatus and method for slowing down printed products as they travel through a rotating bucket assembly section of a folder of a printing press. The rotating bucket assembly typically including at least two rotatable fan wheels which cooperate to provide a plurality of aligned pockets for receiving individual printed products. The slow down apparatus generally includes an arm and a free wheeling member supported by the arm. The free wheeling member is moveable, such as rotatable, upon contact with a printed product. The free wheeling member is positionable by the arm and relative to the fan wheels such that the free wheeling member contacts a portion of the printed product that is already positioned in a pocket.
An exemplary method of the present invention includes the slowing down of printed products in the folder of a printing press by transporting a printed product to the rotating bucket assembly, transferring the printed product into one of the pockets of the rotating bucket assembly and slowing down the speed of the printed product, after the printed product has begun to enter a pocket, with a non-driven member that rotates upon contact with the printed product.
It is one feature of the present invention to provide an improved printed product slow down apparatus and method.
It is another feature of the present invention to provide a printed product slow down apparatus and method that enables a printing press to be operated at high speeds.
It is another feature of the present invention to provide a printed product slow down apparatus and method that reduces the kinetic energy of a moving printed product thus slowing down the printed product.
It is another feature of the present invention to provide a printed product slow down apparatus and method that includes at least one member to absorb kinetic energy of a moving printed product.
It is another feature of the present invention to provide a printed product slow down apparatus and method that includes a free wheeling member that rotates upon contact with a printed product to absorb the kinetic energy of the moving printed product.
It is another feature of the present invention to provide a printed product slow down apparatus and method that includes a free wheeling brush or free wheeling roller than is rotated by a printed product.
It is another feature of the present invention to provide a printed product slow down apparatus and method that reduces the impact speed of a printed products at the dead end of the pocket.
It is another feature of the present invention to provide a printed product slow down apparatus and method that reduces damage to a printed products as they travel into and out of the bucket assemblies.
It is another feature of the present invention to provide a printed product slow down apparatus and method that reduces damage to a printed products as they are slowed down.
It is another feature of the present invention to provide a printed product slow down apparatus and method that slows down a printed products after the printed products have at least partially entered a pocket.
It is another feature of the present invention to provide a printed product slow down apparatus and method that slows down printed products by contacting a portion of the printed products that is already in the pocket of a bucket assembly.
It is another feature of the present invention to provide a printed product slow down apparatus and method that slows down printed products by contacting only one side of the printed products.
It is another feature of the present invention to provide a printed product slow down apparatus and method that does not contact the entire length of the printed products.
It is another feature of the present invention to provide a printed product slow down apparatus and method in which the slow down apparatus is inoperative when the press operating speed is below a predetermined point.
It is another feature of the present invention to provide a printed product slow down apparatus and method in which the slow down apparatus is moved out of the path of the printed products to avoid any contact between the printed products and the slow down apparatus when the press operating speed is below a predetermined point.
It is another feature of the present invention to provide a printed product slow down apparatus and method wherein printed products are slowed after they have been released from the transportation mechanism that brought the printed products to the rotating bucket assembly.
It is another feature of the present invention to provide a printed product slow down apparatus and method wherein the slow down apparatus is located between adjacent fan wheels.
It is another feature of the present invention to provide a printed product slow down apparatus and method wherein the position of the slow down apparatus relative to the bucket assembly is adjustable.
Other features and advantages of the invention will become apparent to those of ordinary skill in the art upon review of the following detailed description, claims, and drawings.